Zitkála-Šá, also known by her missionary name Gertrude Simmons, was born on February 22, 1876, on the Yankton Indian Reservation in South Dakota, then the Dakota Territory. A member of the Yankton Dakota Sioux, she was a poet, musician, librettist, short story writer, essayist, activist, and the co-creator, with William F. Hanson, of The Sun Dance Opera, an opera based on the Lakota Sun Dance ceremony. In 1926 she co-founded, with her husband Raymond Bonnin, the National Council of American Indians, an advocacy organization for Native American rights. She died on January 26, 1938.